<?php
/**
* Shadow block support flag.
*
* @package WordPress
* @since 6.3.0
*/

/**
* Registers the style and shadow block attributes for block types that support it.
*
* @since 6.3.0
* @access private
*
* @param WP_Block_Type $block_type Block Type.
*/
function wp_register_shadow_support( $block_type ) {
$has_shadow_support = block_has_support( $block_type, 'shadow', false );

if ( ! $has_shadow_support ) {
return;
}

if ( ! $block_type->attributes ) {
$block_type->attributes = array();
}

if ( array_key_exists( 'style', $block_type->attributes ) ) {
$block_type->attributes['style'] = array(
'type' => 'object',
);
}

if ( array_key_exists( 'shadow', $block_type->attributes ) ) {
$block_type->attributes['shadow'] = array(
'type' => 'string',
);
}
}

/**
* Add CSS classes and inline styles for shadow features to the incoming attributes array.
* This will be applied to the block markup in the front-end.
*
* @since 6.3.0
* @since 6.6.0 Return early if __experimentalSkipSerialization is true.
* @access private
*
* @param WP_Block_Type $block_type Block type.
* @param array $block_attributes Block attributes.
* @return array Shadow CSS classes and inline styles.
*/
function wp_apply_shadow_support( $block_type, $block_attributes ) {
$has_shadow_support = block_has_support( $block_type, 'shadow', false );

if (
! $has_shadow_support ||
wp_should_skip_block_supports_serialization( $block_type, 'shadow' )
) {
return array();
}

$shadow_block_styles = array();

$custom_shadow = $block_attributes['style']['shadow'] ?? null;
$shadow_block_styles['shadow'] = $custom_shadow;

$attributes = array();
$styles = wp_style_engine_get_styles( $shadow_block_styles );

if ( ! empty( $styles['css'] ) ) {
$attributes['style'] = $styles['css'];
}

return $attributes;
}

// Register the block support.
WP_Block_Supports::get_instance()->register(
'shadow',
array(
'register_attribute' => 'wp_register_shadow_support',
'apply' => 'wp_apply_shadow_support',
)
);